On 12 June, 1987, when U.S. President Ronald Reagan called on Soviet leader Mikhail Gorbachev to tear down the Berlin Wall, some of his staffers thought Mr. Reagan's words were too hostile, and could harm U.S.-Soviet relations.

Lou Cannon, at that time the senior White House correspondent for The Washington Post and later a Reagan biographer, recalls a dispute broke out among the president's advisors about the wording of the speech.

"I don't think Reagan himself was caught up as much in the debate as everyone thinks," said Cannon. "I think Reagan saw the dramatic possibilities of this, but he also had been to see the Berlin Wall before, he'd seen it on an earlier trip and he considered it to be a truly ugly monument to human slavery."

But Reagan approved the speech, and the phrase remained in the text. Cannon had heard Reagan deliver many speeches, but this one was unique. "I was struck by this speech, I still get goosebumps when I hear recordings of it," he said. "He had toured the wall that morning, and if you tour that wall, it's very emotional because you saw this graffitti and these tributes to people who had died crossing the wall."

The speech's location - at the Brandenburg Gate - was also significant. Cannon said most presidential speeches are given in official settings such as auditoriums. But this speech, delivered outdoors by the Berlin Wall with speakers from the East German side trying to silence him, escalated the drama.

"You have this unusual setting where the person giving the speech, Reagan, has deep feelings about it, his emotions are raw because he's just toured the wall and also they're trying to drown him out," said Cannon. "And so all of those things together, it seemed to me, brought out the dramatic quality in Reagan and produced what I think is one of the more stirring moments of his presidency."